* O2 (Oxygen) has a linear structure. It consists of two oxygen atoms bonded together with a double bond.

* O3 (Ozone) has a bent or angular structure. It consists of three oxygen atoms bonded together, with one double bond and one single bond. The molecule has a V-shape with a bond angle of approximately 116.8°.

Here's a simple illustration:

O2: O=O

O3: O=O-O

This difference in structure leads to different properties for the two molecules. For instance, ozone is a powerful oxidizer, while oxygen is essential for respiration.